Articles editing

https://drive.google.com/file/d/1EeEt_vd4fjkgCE9dmnD32OYVtMm2Blb-/view?usp=sharing

When i want to edit articles it’s only possible with the HTML editor. I tried to change it to the visual editor but it does not appear where it should or with shift+ctrl+alt+M. I also tried to desactivate all plugins, change theme, JavaScript, doing it in another broeser and actualization of wordpress (back up and delete files) but nothing changes. What’s the problem and what can I don to solve it?

The page I need help with: [log in to see the link]